Smithsonite
Carbonate · ZnCO₃
Smithsonite is a zinc carbonate, prized by collectors for its smooth, botryoidal crusts in soft blue-green, pink and lavender.
What is smithsonite?
Smithsonite is zinc carbonate that forms in the weathered zones of zinc ore deposits. It is best known for glassy, botryoidal (bubbly) crusts with a slightly pearly sheen in gentle blue-green, pink and lavender pastels. It is denser than it looks and was an early zinc ore.
Properties
- Chemical formula
- ZnCO₃
- Category
- Carbonate
- Hardness (Mohs)
- 4–4.5
- Crystal system
- Trigonal
- Lustre
- Vitreous to pearly
- Streak
- White
- Colour
- Blue-green, pink, yellow, brown
- Cleavage / fracture
- Perfect rhombohedral
How to identify smithsonite
- →Smooth botryoidal crusts with a soft, pearly sheen.
- →Pastel blue-green, pink or lavender colours.
- →Heavier than expected for its size.
- →Fizzes in warm acid; hardness 4–4.5.
Where smithsonite is found
Classic specimens come from Kelly Mine (New Mexico, USA), Tsumeb (Namibia), Mexico, Greece and Sardinia.
Smithsonite finds on minShelf
Real specimens catalogued by collectors.
Think you've found smithsonite?
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